Many machine tools have utilized tool changers and other machine tools have utilized workpiece changers which are a form of robotic control. There has also been known a single machine tool which utilizes both a workpiece changer and a tool changer. One such machine tool utilizes a workpiece changer separate from the tool changer, wherein both move individually on a track or slide, for example, parallel to an axis of a machine tool. In such a mechanism, each of the workpiece changer and tool changer is separately controlled by a programmable control, with all the complexity and expense entailed thereby, and the only common part of the mechanism between these two changers is the slide or trackway on which they both travel. In this prior art, each of the workpiece and tool changers adds several axes of motion, for example, along X, Y, and Z axes, and at least two axes of motion on each changer was a precise positioning control, which may be a servocontrol with a feedback from a resolver to assure that the changer had been precisely positioned. Such controls are quite expensive. This has the disadvantage that the two could possibly crash into each other, and also has the complexity of the proper programmable control of the motions of each.